Abbott-Smith Manual Greek Lexicon
Ἀρέτας (G702)
1 Ἀρέτας (WH, Ἀρ. ; Intr. , 313), -α, ὁ , Aretas , an Arabian king: II Co 11:32 (Deiss., BS , 183 f., thinks the proper spelling Ἀρέθας was changed, as Schürer suggests, "by desire to Hellenise a barbaric name by assimilation to ἀρετή ").†
G. Abbott-Smith, A Manual Greek Lexicon of the New Testament (1922) — public domain